All objects placed in Class A airspace should be required to have ADS-B Out. Without this, it's Tragedy of the Commons until another preventable collision happens again. Notifying authorities offline that some free-floating objects may be in a massive region isn't anywhere close to as good as real-time updates that ADS-B In on commercial aircraft can recognize and avoid. ADB-B In for all aircraft operating in class A should be made mandatory instead of optional for this reason. The peeps will squeak about "cost" and "complexity", but some safety standards need to be advanced before they are written in more than arm blood.
